Since this was a couple of links deep, I thought I'd post it in its own message on this board. It's an old study, but the end result is that 2% of the population studied have daily fasiculations.

Mike

"Muscle Fasciculations in a Healthy Population" which I think comes closest to answer this question, but still leaves much room for speculation. I will quote and summarize parts of the report. I hope it helps you and others. BTW, this report is from 1963!

The first 2 paraqraphs:

"The occurrence of muscle fasciculations in an otherwise healthy person is not regarded as the ominous prelude to a progressive lower motor neuron disease as it was 20 years ago. Several reports document the fact that many persons experience fasciculations over a preiod of years, and the occurrence is without pathological significance.
In regard to this change in clinical impression, it is surprising that no definitive investigation has been made to determine the extent to which healthy persons experience fasciculations. This report is an analysis of the occurrence of benign fasciculations in a large group of healthy medical personnel."

Further:

"Method

Between 1960 and 1962 a 16 mm sound and color film entitled "Amyotrophic Lateral Sclerosis in the Mariana Islands" was shown in medical schools, medical institues, and hospitalsin the United States, Puerto Rico, and the Philippines. This film illustrated typical muscle fasciculations in many patients with amyotrophic lateral sclerosis.
The audiences consisted of medical students, physicians, nurses, and allied medical personnel. Such persons are usually thoroughly screened for health defects and can be considered normal adults.
Before this film was shown, the purpose of the study was explained and the audiences were instructed to observe the fasciculations closely. At the conclusion of the film they were requested to complete a questionnaire concerning their own experiences with fasciculations similar to those shown in the movie. If a person responded positively to the question of having fasciculations, he was requested to complete a section on the details of the fasciculations and associated factors. In order to rule out the possibility of pathological fasciculations, the questionnaire contained a section related to neurological disease. The benign nature of fasciculations was stressed to prevent nonreporting for fear of having a serious motor neuron disease."

A total of 541 subjects answered the questionnaires. Two were discarded because the subjects reported a history of neurological disease. 379 reported muscle fasciculations. Males, females, caucasian, "negro", and oriental were all represented. Now for some tables:

"It should be pointed out that since many subjects reported the duration as less than one minute, the spontaneous termination of the episodes might mistakenly be associated with anything that was done."